I didn't have much trouble setting up the account, and I can call (once I noticed that I had to add a "1" before the phone number).

However, when answer the call, there is no sound going in either direction. Googling "VOIP no sound" turned up some hits that made it sound like I am perhaps just not understanding how VOIP with SIP is supposed to work.

I also tried using "Linphone" on Linux, with the same effect -- dialing "15551234567@sip.voipdiscount.com" resulted in the call going through, but with no sounds...

What might I be missing?